Production facilities (also called production lines) where items to be machined (hereinafter called “machining targets”) are transported on predetermined transport paths and processed by a plurality of processing devices disposed on the transport paths are used for producing various kinds of products. The stated production lines are required to efficiently manufacture the products.
For example, Patent Literature 1 discloses a car body assembly line provided with a main line where attached are main components common to different car bodies and main components capable of absorbing a deviation in attachment-work man-hours generated due to a difference in car types, and a sub-line where attached are main components incapable of absorbing the deviation in the attachment-work man-hours generated due to the difference in car types and sub-components.
Patent Literature 2 discloses an automobile production line where assembly standby vehicle-row lanes and a buffer lane are disposed between a coating line and an assembly line. The buffer lane is configured to align vehicles selected from the assembly standby vehicle-row lanes in a row and feed out the aligned vehicles toward the assembly line on a downstream side; the order in which the vehicles are aligned in the buffer lane is carefully controlled so as to increase the operating ratio of the assembly line.